title: Global view of the functional molecular organization of the avian cerebrum: mirror images and functional columns.
abstract: Based on quantitative cluster analyses of 52 constitutively expressed or behaviorally regulated genes in 23 brain regions, we present a global view of telencephalic organization of birds. The patterns of constitutively expressed genes revealed a partial mirror image organization of three major cell populations that wrap above, around, and below the ventricle and adjacent lamina through the mesopallium. The patterns of behaviorally regulated genes revealed functional columns of activation across boundaries of these cell populations, reminiscent of columns through layers of the mammalian cortex. The avian functionally regulated columns were of two types: those above the ventricle and associated mesopallial lamina, formed by our revised dorsal mesopallium, hyperpallium, and intercalated hyperpallium; and those below the ventricle, formed by our revised ventral mesopallium, nidopallium, and intercalated nidopallium. Based on these findings and known connectivity, we propose that the avian pallium has four major cell populations similar to those in mammalian cortex and some parts of the amygdala: 1) a primary sensory input population (intercalated pallium); 2) a secondary intrapallial population (nidopallium/hyperpallium); 3) a tertiary intrapallial population (mesopallium); and 4) a quaternary output population (the arcopallium). Each population contributes portions to columns that control different sensory or motor systems. We suggest that this organization of cell groups forms by expansion of contiguous developmental cell domains that wrap around the lateral ventricle and its extension through the middle of the mesopallium. We believe that the position of the lateral ventricle and its associated mesopallium lamina has resulted in a conceptual barrier to recognizing related cell groups across its border, thereby confounding our understanding of homologies with mammals.
authors.affiliation: Department of Neurobiology, Howard Hughes Medical Institute, Duke University Medical Center, Durham, North Carolina, 27710.
authors.forename: Erich D
authors.initials: ED
authors.lastname: Jarvis
authors.forename: Jing
authors.initials: J
authors.lastname: Yu
authors.forename: Miriam V
authors.initials: MV
authors.lastname: Rivas
authors.forename: Haruhito
authors.initials: H
authors.lastname: Horita
authors.forename: Gesa
authors.initials: G
authors.lastname: Feenders
authors.forename: Osceola
authors.initials: O
authors.lastname: Whitney
authors.forename: Syrus C
authors.initials: SC
authors.lastname: Jarvis
authors.forename: Electra R
authors.initials: ER
authors.lastname: Jarvis
authors.forename: Lubica
authors.initials: L
authors.lastname: Kubikova
authors.forename: Ana E P
authors.initials: AE
authors.lastname: Puck
authors.forename: Connie
authors.initials: C
authors.lastname: Siang-Bakshi
authors.forename: Suzanne
authors.initials: S
authors.lastname: Martin
authors.forename: Michael
authors.initials: M
authors.lastname: McElroy
authors.forename: Erina
authors.initials: E
authors.lastname: Hara
authors.forename: Jason
authors.initials: J
authors.lastname: Howard
authors.forename: Andreas
authors.initials: A
authors.lastname: Pfenning
authors.forename: Henrik
authors.initials: H
authors.lastname: Mouritsen
authors.forename: Chun-Chun
authors.initials: CC
authors.lastname: Chen
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Wada
mesh_terms: D000818:Animals; D001717:Birds / Q000033:anatomy & histology*; D002452:Cell Count; D054022:Cerebrum / Q000033:anatomy & histology* / Q000378:metabolism*; D015870:Gene Expression; D021621:Imaging, Three-Dimensional; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D059906:Neuroimaging; D009474:Neurons / Q000378:metabolism; D013045:Species Specificity
chemical_list: D009419:Nerve Tissue Proteins
keywords: amygdala; basal ganglia; brain evolution; brain organization; brain pathways; claustrum; cortex; forebrain; immediate early genes; motor behavior; neural activity; neurotransmitter receptors; pallidum; pallium; primary sensory; striatum